American John Isner extended his 2012 clay court winning streak to six matches on Friday to advance to Saturday’s semifinal where he will face Spain’s Feliciano Lopez.
Isner needed two tie-breaks to get past defending champion Ryan Sweeting 7-6(4) 7-6(1), while Lopez moved on with a 6-4 2-2 win after Carlos Berlocq retired with a lower leg injury.
The victories set up a battle between a pair of Top 15 players in Saturday semifinals. Lopez, who is No. 15, defeated No. 10 Isner in five sets during the Australian Open in their last meeting.
For both players, reaching this round is a breakthrough. For Isner, it is his first career semifinal on clay, while Lopez has reached his first semifinal in 2012.
Isner six victories on clay this year have come in a pair of matches in away Davis Cup ties against Switzerland and France in addition to his two match wins this week in Houston.
There is extra incentive for Isner to win Saturday’s match – by doing so he would become the No. 1 ranked American, swapping rankings positions with No. 9 Mardy Fish.